A bluetooth smart key device is a smart key device with a bluetooth, which uses two-factor authentication, and it is more convenient and costs less for a user. A single chip microcontroller or a smart key device chip is installed in a smart key device for storing a smart key or a digital certificate of a user, thus, it can authenticate the user's ID by using a cipher algorithm in the smart key device; the smart key device has multiple functions, such as encrypting an E-mail, digital signature, security certificate, logging in a security network and access to an SSL security network. Besides, the smart key device is very secure because it has a characteristic of ensuring that a private key of the user is always with hardware and a characteristic of anti-attack physically.
In prior art, each time the smart key device is started, it can be searched by other mobile devices, and it is connected to the mobile devices passively, which is not safe because the smart key device cannot prevent a malicious mobile device from using the device for trade.